KEO 3-flute center reamers are versatile tools designed for countersinking holes for centers or for enlarging existing holes. Also available in a 5-piece set. Cobalt steel tools are similar to high-speed steel, but with more cobalt for improved performance when cutting harder metals such as stainless steel or nickel alloys. Titanium nitride coatings add a hard layer of gold-colored ceramic to the surface that extends tool life and permits faster cutting speeds than uncoated tools. Round shanks allow use with a wide variety of toolholding systems. When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging. 90 degree angle.